Main AWS. This is the FARS (Fan Aspirated Radiation Shield) version of the Vantage Pro 2 AWS, the fan aspiration reduces risk of over heating on calm days with strong sunshine and improves sensor response. This unit also contains the onboard sensor suite - handling rainfall, screen temp, dew point, humidity. Communication with console is by wireless link. Power supply is via solar panel and rechargable battery (charged duirng daylight by solar panel).